1. Technical Field
The invention relates generally to devices and methods for Machine to Machine communication, and more particularly, to devices and methods for access procedure enhancements.
2. Related Art
Machine to Machine (M2M) communication is defined as the information exchange between a subscriber station (or a wireless communication device) and a server in the core network, or just between subscriber stations, which may be carried out without any human interactions. Due to the potential of M2M communication technologies, enhancements for enabling M2M communications are being developed for wireless access networks, such as Global System for Mobile Communication/General Packet Radio Service (GSM/GPRS), Universal Mobile Telecommunication System (UMTS), 1x Code Division Multiple Access 2000 (1x CDMA 2000) system, 1x High Rate Packet Data (1xHRPD) system, and Long Term Evolution (LTE) system, etc.
However, an access channel used by most M2M terminals to transmit the data traffic is a shared common channel for all M2M terminals in the same service area. Moreover, since most M2M communication is module driven, access collisions can be caused by the access dimension limit as module penetration is increased. Due to access collisions, the reverse link (RL) rise over thermal (RoT) as well as report/control delay are increased, while RL capacity and module battery life are decreased. Therefore, it is desirable to have access probes which minimize the impact on the existing services when M2M terminals increase, and improve the access success rate of the M2M terminals. The challenges, on the other hand, include the RoT contribution from the M2M terminals, the potential dimension limit of the current RL channels, as well as other related problems such as macro-diversity and the detection complexity dilemma, network imbalance, and the load and throughput dilemma. Additional considerations may also include implementation, network positioning, and terminal battery life improvement.